Method and apparatus for performing a minimally invasive total hip arthroplasty

ABSTRACT

A method and apparatus for performing a minimally invasive total hip arthroplasty. An approximately 3.75-5 centimeter (1.5-2 inch) anterior incision is made and the femoral neck is severed from the femoral shaft and removed through the anterior incision. The acetabulum is prepared for receiving an acetabular cup through the anterior incision, and the acetabular cup is placed into the acetabulum through the anterior incision. In one exemplary embodiment, a posterior incision of approximately 2-3 centimeters (0.8-1.2 inches) is generally aligned with the axis of the femoral shaft and provides access to the femoral shaft. In this embodiment, Preparation of the femoral shaft including the reaming and rasping thereof is performed through the posterior incision, and the femoral stem is inserted through the posterior incision for implantation in the femur. In an alternative embodiment, preparation of the femur is effected through the anterior incision, with the operative hip placed in hyperextension.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This is a continuation-in-part of co-pending application Ser. No.10/053,931, filed Jan. 22, 2002 and published as U.S. Publication No.US2002/0116067 A1, on Aug. 22, 2002, the disclosure of which is herebyexplicitly incorporated by reference herein, which is acontinuation-in-part of co-pending application Ser. No. 09/558,044 filedApr. 26, 2000, the disclosure of which is hereby explicitly incorporatedby reference herein.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to total hip arthroplasty, and,more particularly, to a method and apparatus for performing a minimallyinvasive total hip arthroplasty.

[0004] 2. Description of the Related Art

[0005] Orthopaedic procedures for the replacement of all, or a portionof, a patient's joint have been developed over the last 30 years.Currently, the procedures used to prepare the bone and seat the implantsare generally referred to as open procedures. For the purpose of thisdiscussion, the term open procedure will refer to a procedure wherein anincision is made through the skin and underlying tissue to fully exposea large portion of the particular joint surface. In the case of a totalhip arthroplasty, the typical incision required is approximately 25centimeters (10 inches) long. After the initial incision in the skin,the internal wound may be enlarged in order to fully expose the areas tobe prepared. While this approach provides surgeons with an excellentview of the bone surface, the underlying damage to the soft tissue,including the muscles, can lengthen a patient's rehabilitation timeafter surgery. While the implants may be well fixed at the time ofsurgery, it may be several weeks or perhaps months before the softtissues violated during surgery can be fully healed.

SUMMARY OF THE INVENTION

[0006] The present invention provides an improved method and apparatusfor performing a minimally invasive total hip arthroplasty. A total hiparthroplasty can be performed in accordance with the teachings of thecurrent invention utilizing two incisions with the size of each of thewounds developed on the surface being substantially constant throughoutthe depth of the wound. The first incision is an anterior incisionapproximately 3.75-5 centimeters (1.5-2 inches) in length made in linewith the femoral neck and the central axis of the acetabulum. The secondincision is a posterior incision approximately 2.5-3.75 centimeters(1-1.5 inches) positioned to be generally in axial alignment with thefemoral shaft. In an alternative embodiment, the anterior incisionbegins at the intertrochanteric ridge and is extended inferiorly andmedially generally on the line along which the femoral neck will besevered from the femur. In this embodiment, the anterior incision ismade in line with the Langer's lines in the skin and therefore leads toless scarring. In the alternative embodiment, the posterior incision isaligned with the femoral shaft and is generally colinear with theanterior incision. In this way, the anterior incision and the posteriorincision can be connected to allow for an open procedure in the eventthat a minimally invasive procedure is planned but an open procedure isdetermined to be necessary.

[0007] The femoral head is severed from the femoral shaft and removedthrough the anterior incision. The acetabular cup is placed in theacetabulum through the anterior incision, while the posterior incisionis used to prepare the femoral shaft to receive a femoral stem. Afemoral stem is inserted through the posterior incision and positionedin the femoral shaft. Procedures performed through the posteriorincision may be observed through the anterior incision and vice versa.

[0008] For the purpose of the following discussion, a total hiparthroplasty is defined as a replacement of the femoral head with orwithout the use of a separate acetabular component. The specific designswhich can be utilized in accordance with the present invention include atotal hip replacement and a bipolar or monopolar endo prosthesis. Thetechnique is suitable for cemented or cementless anchorage of thecomponents.

[0009] The apparatus and method of the current invention advantageouslyallow a total hip arthroplasty to be performed in a minimally invasiveway, which hastens patient recovery.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The above-mentioned and other features and advantages of thisinvention, and the manner of attaining them, will become more apparentand the invention itself will be better understood by reference to thefollowing description of an embodiment of the invention taken inconjunction with the accompanying drawings, wherein:

[0011]FIG. 1A is a side elevational view of a patient illustrating apair of incisions made according to the current invention as well as theincision utilized in prior art procedures;

[0012]FIG. 1B is a side elevational view of a patient illustrating analternative pair of incisions made according to the current invention aswell as a line joining the incision pair along which a third incisioncan be made to join the incision pair and convert the procedure from aminimally invasive procedure to an open procedure;

[0013]FIG. 2A is an anterior elevational view of a hip jointillustrating the femoral neck axis;

[0014]FIG. 2B is an anterior elevational view of a hip jointillustrating the line along which the femoral neck will be severed fromthe femur and further illustrating the location of anterior incision 44′depicted in FIG. 1B;

[0015]FIG. 2C is an anterior elevational view illustrating the capsuleof the hip joint;

[0016]FIG. 3 is an anterior elevational view of the femoral neck exposedby incising the hip capsule;

[0017]FIG. 4 is an anterior elevational view of the femoral neck with anosteotomy guide of one form of the current invention operably positionedto designate a cut line thereon;

[0018]FIG. 5A is a side elevational view of an alternative embodiment ofan osteotomy guide in accordance with the present invention;

[0019]FIG. 5B is an elevational view thereof taken along thelongitudinal axis of the handle;

[0020]FIG. 6A is an anterior elevational view illustrating the femoralhead and neck severed along the cut line indicated by the osteotomyguide;

[0021]FIG. 6B is an anterior elevational view illustrating the femoralhead and neck severed along the cut line illustrated in FIG. 2B andfurther illustrating the line along which the femoral head is severedfrom the femoral neck in accordance with one embodiment of the presentinvention;

[0022]FIG. 7 is an anterior elevational view illustrating the removal ofa portion of the femoral head and neck;

[0023]FIGS. 8A and 8B illustrate preparation of the acetabulum toreceive the acetabular cup;

[0024]FIG. 9 is a side elevational view of an acetabular cup inserterrelative to a patient lying in the supine position;

[0025]FIG. 10 is an anterior elevational view of a portion of the cupinserter illustrated in FIG. 9 and a patient lying in the supineposition;

[0026]FIG. 11 is a side elevational view illustrating the use of acurved awl to locate a posterior incision;

[0027]FIG. 12 is a side elevational, partial sectional view of an awl inaccordance with the present invention;

[0028]FIG. 13 is a perspective view illustrating the insertion of aposterior retractor in the posterior incision;

[0029]FIG. 14 is a perspective, exploded view of one embodiment of atubular retractor in accordance with the present invention;

[0030]FIG. 14A is a side elevational view of an alternative embodimentof the tubular retractor;

[0031]FIG. 15 is a perspective view illustrating the insertion of aguide wire into the tubular retractor;

[0032]FIG. 16 is a perspective view illustrating reaming of the femoralshaft;

[0033]FIG. 17A is a perspective view of an end cutter;

[0034]FIG. 17B is a perspective view of a femoral reamer;

[0035]FIG. 18 is a side elevational, partial sectional view of an endcutter inserted into a tubular retractor of the present invention;

[0036]FIG. 19 is a perspective view of a rasp handle after inserting arasp into the femoral shaft;

[0037]FIG. 19A is a perspective view illustrating an inserted rasp, withthe rasp handle removed, and with the cable used to affix the rasp tothe rasp handle protruding from the posterior incision;

[0038]FIGS. 20A and 20B are partial sectional views of the rasp handle;

[0039]FIG. 21 is an exploded view of the rasp handle and a rasp to beconnected thereto;

[0040]FIG. 21A is a partial elevational view along line 21A-21A of FIG.21;

[0041]FIG. 22 is a perspective view illustrating placement of aprovisional neck of the present invention;

[0042]FIG. 23 is a perspective view of the provisional neck and matingforceps of the present invention;

[0043]FIG. 24A is a partial sectional, radial elevational view of theprovisional neck;

[0044]FIGS. 24B and 24C are radial elevational views thereof;

[0045]FIG. 25 is a perspective view illustrating the insertion of afemoral stem with a protective bag through the posterior incision;

[0046]FIG. 26 is a perspective view illustrating alignment of thefemoral stem while observing through the anterior incision;

[0047]FIG. 27 illustrates an incision into the femoral stem protectivebag prior to insertion of the femoral stem into the femoral shaft;

[0048]FIG. 28 is a perspective view illustrating removal of the femoralstem protective bag while inserting the femoral stem, with observationthrough the anterior incision;

[0049]FIG. 29 is a perspective view of a femoral stem insertion tool inaccordance with the teachings of the present invention;

[0050]FIG. 30 is a perspective view of a hip prosthesis which can beimplanted according to the method of the current invention;

[0051]FIG. 31 is a perspective view of an alternative embodiment rasphandle in accordance with the present invention.

[0052]FIG. 32 is a side elevational view thereof;

[0053]FIG. 33 is a top elevational view thereof;

[0054]FIG. 34 is a sectional view illustrating a rasp secured to therasp handle;

[0055]FIG. 35 is a sectional view illustrating release of the lockingmechanism used to secure a rasp to the rasp handle;

[0056]FIG. 36 is a sectional view of the impaction surface of the rasphandle illustrated in FIGS. 31-35;

[0057]FIG. 37 is an exploded perspective view of a cup inserter of thepresent invention;

[0058]FIG. 38 is a side plan view thereof;

[0059]FIG. 39 is a partial sectional view of the distal portion of theframe of the cup inserter illustrated in FIGS. 37 and 38;

[0060]FIG. 40 is a sectional view of a threaded shaft used to engage anacetabular cup in conjunction with the cup inserter illustrated in FIGS.37 and 38;

[0061]FIG. 41 is a sectional view thereof;

[0062]FIG. 42 is a side elevational view of a connecting shaft of thecup inserter illustrated in FIGS. 37 and 38;

[0063]FIG. 43 is a sectional view thereof;

[0064]FIG. 44 is an end elevational view thereof;

[0065]FIG. 45A is a sectional view taken along line 45A-45A of FIG. 42;

[0066]FIG. 45B is a sectional view taken along line 45B-45B of FIG. 42;

[0067]FIG. 46 is an exploded perspective view of another acetabular cupinserter in accordance with the present invention;

[0068]FIG. 47 is a radial elevational view of a threaded shaft used toengage an acetabular cup in conjunction with the cup inserterillustrated in FIG. 46;

[0069]FIG. 48 is an axial elevational view thereof;

[0070]FIG. 49 is a radial elevational view of a U-joint linkage inaccordance with the present invention;

[0071]FIG. 50 is a second radial elevational view thereof, rotated 90°with respect to FIG. 49;

[0072]FIG. 51 is a top elevational view of a locking lever in accordancewith the present invention;

[0073]FIG. 52 is a side elevational view thereof;

[0074]FIG. 53 is a radial elevational view of a locking shaft inaccordance with the present invention;

[0075]FIG. 54 is a sectional view thereof taken along line 54-54 of FIG.53;

[0076]FIG. 55 is an axial elevational view of the locking shaft depictedin FIG. 53;

[0077]FIG. 56 is a perspective view of an operating table in accordancewith the present invention;

[0078]FIG. 57 is a top elevational view thereof;

[0079]FIG. 58 is a side elevational view thereof;

[0080]FIG. 59 is a side elevational view thereof illustrating a patientpositioned atop the operating table of the present invention;

[0081]FIG. 60 is a side elevational view of the operating table of thepresent invention illustrating use of a buttocks door to allow forextension of the patient's buttocks through the table top;

[0082]FIG. 61 is a side elevational view illustrating rotation of a legpanel of the operating table of the present invention to allow forhyperextension of the patient's hip;

[0083]FIG. 62 is an anterior elevational view of the osteotomizedfemoral neck viewed through an anterior incision made in accordance withthe present invention, with the operative leg placed in hyperextension;and

[0084]FIG. 63 is radial elevational view of a lateralizing reamer of thepresent invention.

[0085] Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplification set out hereinillustrates one preferred embodiment of the invention, in one form, andsuch exemplification is not to be construed as limiting the scope of theinvention in any manner.

[0086] Throughout this document “proximal” and “distal” are sometimesused to refer to opposite ends of instruments described herein. Whenreferring to the opposite ends of instruments, “proximal” and “distal”are used with reference to a user of the instrument. For example, theend of the instrument nearest the user during use thereof is describedas the proximal end, while the end of the instrument farthest from theuser during use is described as the distal end of the instrument.

DETAILED DESCRIPTION OF THE INVENTION

[0087] A total hip arthroplasty can be performed, according to theteachings of the current invention through two incisions, each no morethan 5 centimeters (2 inches) in length. An anterior incision is madeeither along the axis of the femoral neck or aligned with the line alongwhich the femur will be osteotomized to remove the femoral neck, while aposterior incision is made generally in axial alignment with the femoralshaft. Referring to FIG. 1A, a partial illustration of patient 40including torso 52, buttock 50, and leg 48 illustrates prior artincision 42 as well as exemplary anterior incision 44 and exemplaryposterior incision 46 of the current invention. Prior art incision 42 isapproximately 25 centimeters (10 inches) long, while anterior incision44 and posterior incision 46 are each no more than 5 centimeters (2inches) in length. Referring to FIG. 1B, a partial illustration ofpatient 40′ including torso 52′, buttock 50′, and leg 48′ is used toillustrate exemplary anterior incision 44′ and exemplary posteriorincision 46′ of the current invention. Anterior incision 44′ andposterior incision 46′ are each no more than 5 centimeters (2 inches) inlength. As illustrated in FIG. 1B, anterior incision 44′ and posteriorincision 46′ are generally colinear and can be joined along line 47 toallow for a minimally invasive hip procedure to be altered to an openprocedure.

[0088] According to the method of total hip arthroplasty of the currentinvention, patient 40 is initially placed in a supine position on anoperating table. A standard operating table or a radiolucent table canbe used. In one exemplary embodiment, operating table 400 illustrated inFIGS. 56-61 is utilized. Operating table 400 includes a table top whichis completely radiolucent, i.e., no portion of the table top ofoperating table 400 is radiopaque. Operating table 400 will be describedin further detail hereinbelow. A radiolucent table is preferred if thesurgical team intends to use intraoperative image intensification. Inone exemplary embodiment, fluoroscopic images are taken repeatedly takenthroughout the procedure to confirm proper positioning of instruments,and implants. In alternative embodiments, endoscopic images can betaken. A Storz viewsite endoscopic system provides a sterile viewingscreen for endoscopic images. The sterile viewing screen of a Storzviewsite endoscopic system can be positioned within the surgical fieldimmediately adjacent to anterior incision 44 or 44′. Other knownendoscopic systems may further be utilized during the total hiparthroplasty of the present invention.

[0089] Referring now to FIG. 2A, with ipsilateral leg 48 in a neutralposition, two prominent bony landmarks are palpated, anterior superioriliac spine (ASIS) 59 and greater trochanter 58 of femur 62. Ilium 64and pubis 66 of hip 68 are shown to better illustrate the relevant areaof the body. In one exemplary embodiment, the approximate anteriorincision starting point 71 is identified two fingerbreadths inferior andtwo fingerbreadths anterior to the tubercle of the greater trochanter58. The approximate finish point for the anterior incision is identifiedthree fingerbreadths inferior and two fingerbreadths lateral to theanterior superior iliac spine (ASIS) 59. In another exemplaryembodiment, the approximate anterior incision starting point 71 isidentified 3-4 centimeters inferior and 2 centimeters lateral to ASIS59. Having identified starting point 71 3-4 centimeters inferior and 2centimeters lateral to ASIS 59, the path of anterior incision 44 isextended obliquely from starting point 71 toward the prominence ofgreater trochanter 58 along the axis of femoral neck 60. With the use ofa spinal needle, the appropriate starting point 71 and the path of theanterior incision can be identified by impaling the skin down to bone toconfirm the central axis 70 of femoral neck 60. In one exemplaryembodiment, a metal, or other radiopaque marker can be positioned overthe identified path of anterior incision 44 and a fluroscopic imagetaken to confirm the appropriate position of anterior incision 44. Ifanterior incision 44′ (FIG. 1B) is utilized, then starting point 71′(FIG. 2B) can be identified by palpating intertrochanteric ridge 59 andextending the incision obliquely as illustrated in FIG. 2B. The positionof intertrochanteric ridge 59 can be confirmed by impaling the skin downto the bone with, e.g., a spinal needle. The location of anteriorincision 44′ can further be confirmed by placing a metallic or otherwiseradiopaque instrument over line 61 illustrated in FIG. 2B and taking afluoroscopic image. After confirmation of the path of anterior incision44 or 44′, a surgical marker can be utilized to mark the location ofsame on the patient's skin.

[0090] If anterior incision 44 is utilized, an oblique incision ofapproximately 3.75-5 centimeters (1.5-2 inches) is made from thestarting site 71 toward the prominence of the greater trochanter alongthe axis 70 of the femoral neck 60 and the central axis of acetabulum 54to form anterior incision 44 as illustrated, e.g., in FIG. 1A. Ifanterior incision 44′ is utilized, an oblique incision of approximately3.75-5.0 centimeters (1.5-2.0 inches) is made from starting site 71′ andextended obliquely along line 61 illustrated in FIG. 2B. The anteriorincision (44 or 44′) is extended along the same plane throughsubcutaneous tissues, exposing the underlying fascia lata. Theinternervous plane between the tensor fascia lata muscle and thesartorius is identified by palpation and developed by curved scissorsand blunt dissection. The sartorius can be made more prominent byexternally rotating the leg to apply tension on the muscle. Deep to thetensor fascia lata and the sartorius is an internervous interval betweenthe rectus femoris and the gluteus medius. This plane is developed byblunt dissection. A lateral retraction of the tensor fascia lata permitsa visualization of the capsule 74 of the hip joint as illustrated inFIG. 2C. In this way, the hip capsule is exposed without requiring theincision of muscle. In some cases the indirect head of the rectusfemorus will be taken down to expose the hip capsule, but it isgenerally very easy to elevate the rectus femorus from the capsulewithout damaging it and expose the hip capsule with no violation ofmuscle. After dissecting below the tensor fascia lata, the precapsularfat and lateral circumflex vessel that travels across the front of thecapsule are exposed. The circumflex vessels may present as one or 2larger arteries and veins, or multiple smaller vessels. If thecircumflex vessels are relatively large, they can be ligated to preventbleeding during reaming of the acetabulum. If they are smaller, they canbe cauterized.

[0091] Leg 48 is externally rotated to create tension on capsule 74.Capsule 74 is incised along the axis 70 (FIG. 2A) of femoral neck 60from the equator of femoral head 56 to the intertrochanteric ridge offemur 62. In one exemplary embodiment, the capsular incision takes theform of an “H-shaped” window formed by incisions 72 (FIG. 2C). TheH-shaped window is formed by adding supplementary perpendicular limbsaround the equator of femoral head 56 and the base of femoral neck 60 tothe initial incision along the axis 70 of femoral neck 60. As a form ofretraction, heavy sutures can be used to provisionally attach thecapsular flaps 73 to the subcutaneous tissues. In alternativeembodiments, the capsular incision is formed as a T-shape, or as alinear incision. In certain embodiments, a triangular portion of thecapsule can be removed. As illustrated in FIG. 3, retractors 76 areplaced inside capsular flaps 73 and underneath the superior and inferiorborders of femoral neck 60 to expose the entire length of femoral neck60 from the inferior aspect of femoral head 56 to the intertrochantericridge. Retractors 76 can be, e.g., Cobra retractors. In one exemplaryembodiment, each retractor houses a light source and can also serve toanchor an endoscope. Retractors 76 thereby provide continuousvisualization and illumination of the wound. In one exemplaryembodiment, JAKOSCOPE retractors having integral fiberoptic lightsources are utilized in accordance with present invention.

[0092] Referring now to FIG. 4, a femoral cutting tool 86, e.g., areciprocating saw, oscillating saw or a power burr is used to excisefemoral neck 60. A custom osteotomy guide 78 can be placed throughanterior incision 44 (FIG. 1A) or 44′ (FIG. 1B) to guide the femoralneck cut. Alignment portion 82 of osteotomy guide 78 is aligned with thelongitudinal axis of femur 62, while cut guide 84 is positioned onfemoral neck 60. Handle 80 of osteotomy guide 78 facilitates positioningand repositioning of osteotomy guide 78 through anterior incision 44 or44′. After placement of osteotomy guide 78, cut line 85 is scored as isknown in the art. Osteotomy guide 78 is thereafter removed throughanterior incision 44 or 44′ and femoral cutting tool 86 is insertedthrough anterior incision 44 or 44′ and utilized to cut along cut line85 and displace portion 88 (FIGS. 6A and 6B) from femur 62. If anteriorincision 44′ is utilized, it will be aligned with the osteotomy utilizedto displace portion 88 from femur 62. In this way, anterior incision 44′may allow for less soft tissue irritation when osteotomizing cut portion88 from femur 62 because the oscillating saw will move in line withanterior incision 44′.

[0093] Retractors 76 are repositioned around the anterior and posteriorrims of the acetabulum. A custom curved cutting tool. (i.e., the“ligamentum teres cutter”) is passed behind femoral head 56 to sharplyincise the ligamentum teres, thus mobilizing cut portion 88 asillustrated in FIG. 6A. Cut portion 88 includes femoral head 56 as wellas a portion of femoral neck 60 (FIG. 4). Cut portion 88 is thereafterremoved through anterior incision 44 with a custom femoral head bonegrasper 94 (FIG. 7). If there is difficulty removing cut portion 88 inone piece, it may be in situ morselized using cutting tool 87 (FIG. 6A),e.g., a power burr. Morsels 92 may then be removed through anteriorincision 44 as illustrated in FIG. 7. Morselizing of cut portion 88 canbe accomplished making cuts which substantially mirror the cuts in hipcapsule 74. In one exemplary embodiment,. a corkscrew and hip skidremoves the entire femoral neck, as in hip fracture. In an alternativeembodiment, femoral head 56 is severed along cut line 63 (FIG. 6B) priorto incising the ligamentum teres. In this embodiment, the osteotomizedfemoral neck is removed before incising the ligamentum teres. Asdescribed above, femoral head 56 may be in situ to morselized tofacilitate removal thereof as necessary. A threaded Steinman pin or aShanz screw can be utilized to remove the osteotomized femoral neck andhead. Irrigation and suction devices can be used to cool the bone andfacilitate the removal of bony debris in hip capsule 74. In oneexemplary embodiment, a fiberoptic endoscope is placed into the hipjoint to confirm the complete removal of bony debris.

[0094] As illustrated in FIG. 8A, the fibro-fatty tissue within thecotyloid fossa of acetabulum 54 is removed with the use of, e.g.,high-speed acorn-tipped cutting tool 96, Rongeur forceps, and a curette.Thereafter, the acetabular labrum can be trimmed with a scalpel. Asillustrated in FIG. 8B, acetabulum 54 is then progressively reamed withstandard acetabular reamer 98. In an alternative embodiment, acustomized minimally invasive reamer such as the one disclosed inco-pending U.S. patent application Ser. No. 10/153,053, filed May 21,2002, the disclosure of which is hereby explicitly incorporated byreference herein, can be utilized to progressively ream acetabulum 54.Acetabular reamers within a predetermined size range are utilized untilthe optimal size of the acetabulum is reached. Sizing of the acetabulumis facilitated by the use of pre-operative templates and radiographs asis known in the art. A fluoroscope, or endoscope can be used to aid invisualization during the reaming process. In certain instances, multiplefluoroscopic or endoscopic images are taken during the reaming processto confirm that when reaming is complete the reamer is bottomed out andis concentric with the acetabulum. Typically the acetabulum is underreamed by approximately 2 mm with respect to the diameter of theanticipated acetabular cup so as to create an interference fit. Highspeed acorn-shaped cutting tool 96, and acetabular reamer 98 enter thebody through anterior incision 44 or 44′.

[0095] After a trial fitting, a press-fit acetabular cup of theappropriate size can be firmly seated with cup inserter 100 asillustrated in FIG. 9 and impacted into the acetabular recess as isknown in the art. In alternative embodiments, acetabular cup inserters360, 360′ (FIGS. 9B, 37-55) may be utilized to seat an appropriateacetabular cup. Cup inserters 360 and 360′ are further describedhereinbelow. If a balloon is positioned under the hip and inflatedduring the total hip arthroplasty of the present invention, it can bedeflated when determining proper alignment for seating of the acetabularimplant. Acceptable press fit acetabular cups include the ZIMMER HGP IIor TRILOGY cups. Proper positioning of the acetabular cup can beachieved with a custom anteflexion and pelvic alignment guide asillustrated in FIG. 9A. Patient 40 is placed in supine position onoperating table 102. Aligning rod 104 is aligned with the mid lateralaxis of torso 52 while main shaft 105 is maintained approximately 30°from operating table 102 for proper seating of the acetabular cup. Toaugment fixation of the cup, a flexible drill can be used to guide theplacement of one or more acetabular screws. In some cases, acetabularscrews will not be necessary. The insertion of the acetabular liner is,in certain embodiments, deferred until the proximal femur has beenprepared for the insertion of a trial stem. As illustrated by theanterior elevational view of FIG. 10, patient 40 remains in the supineposition on operating table 102 (FIG. 9) while cup inserter 100 isutilized to seat the acetabular cup. Similarly, patient 40 remains inthe supine position on operating table 102 if either of cup inserters360, 360′ are utilized to seat the acetabular cup.

[0096] For preparation of the femur, the patient is repositioned with apad, e.g., an inflatable pad placed under the ipsilateral hip. In oneexemplary embodiment, an inflatable pad is placed under the hip andinflated at the beginning of the procedure. With an inflatable pad inplace under the hip and inflated, the femur will drop below theacetabulum when the femoral neck is osteotomized giving better access toboth the acetabulum and the femur. The operative hip is slightly flexedor extended, adducted approximately 30° to 45°, and maximally externallyrotated or rotated to approximately 30° to 45°. In one exemplaryembodiment, an operating table having movable leg panels is utilized. Inthis embodiment, the non-operative leg can be dropped below theoperative leg prior to position the operative hip for preparation of thefemur (e.g., extending, adducting, and rotating the operative hip). Whenthe non-operative knee is lowered, i.e., the non-operative hip ishyperextended, the operative hip is effectively raised, whichfacilitates preparation of the femur as described below. Retractors 76are repositioned around the medial and lateral aspects of femur 62.Alternatively, a self-retaining retractor with a light source attachmentand an endoscope holder can be positioned in anterior incision 44 toprovide constant visualization and illumination of femur 62.

[0097] In one embodiment, the soft tissues along the anterior surface offemur 62 just inferior to the intertrochanteric ridge aresubperiosteally reflected with a scalpel or curved osteotome to exposethe bone for a width of approximately 1 cm. This sharp subperiostealelevation continues superolaterally onto the anterior margin of thegreater trochanter. Then with curved Mayo scissors a pathway isdeveloped by blunt dissection that is directed superficially to theanterior fibers of the gluteus minimus towards buttock 50 (FIG. 11). Inan alternative embodiment, the osteotomized femoral neck is visualizedthrough the anterior incision and any remaining superolateral femoralneck is removed. Curved Mayo scissors are then directed posterior to theposterior neck of the femur just superior to the insertion of thepiriformis tendon. If the piriformis tendon traverses this site, it isdivided with the scissors. the scissors are advanced through theposterior capsule and toward the gluteus maximus. To assist in thedirection of the scissors, a line can be drawn along the front axis ofthe femur and along the side axis. Where the two lines intersect on thesuperolateral aspect of the hip is the appropriate site for theposterior as is further described herein below.

[0098] As illustrated in FIG. 11, awl 106 is inserted through anteriorincision 44, directed through the cleft between the gluteus medius andmaximus in line with the shaft of the femur and piriformis fossaeregion, and advanced into the soft tissues of buttock 50 until itspointed distal end 108 can be palpated on the surface of the skin.Distal end 108 of awl 106 is generally aligned with the longitudinalaxis of femur 62. At the point where distal end 108 is palpated,posterior incision 46 or 46′ of approximately 2-3 cm (0.8-1.2 inches) ismade and extended through the subcutaneous tissues and fascia lata toexpose the underlying gluteus maximus. In one exemplary embodiment, asurgical marking pen can be used to draw a line on the skin down thefront of the femur and a line on the skin along the side of the femur.The intersection of these two lines will generally mark the position ofthe posterior incision. A tract to femur 62 is developed along the pathcreated by awl 106. Generally, the gluteus maximus is split bluntly inline with its fibers with curved Mayo scissors. Finger dissection may beutilized to reach the posterior piriformis fossa region. In certaincases the piriformis obstructs the view of the femur. In these cases,the piriformis can be divided. In many instances, the piriformis isinferior to the femur and does not require division. Into this pathway,via posterior incision 46 or 46′, custom elliptical posterior retractor122, complete with its inner sleeves, can be threaded (FIG. 13) down tothe osteotomized femoral neck. In one exemplary embodiment, ellipticalposterior retractor 122 includes posterior lip 128 (FIG. 14). In thisembodiment, retractor 122 is threaded down to the osteotomized femoralneck until posterior lip 128 lies beneath the posteriorintertrochanteric ridge. FIG. 14A illustrates an embodiment of rasptunnel 130 without posterior lip 128. In an alternative embodiment, eachcomponent of posterior retractor 122 (i.e., guide tube 124, reamertunnel 126, and rasp tunnel 130) is individually inserted and removed asnecessary. In an embodiment in which guide tube 124, reamer tunnel 126,and rasp tunnel 130 are individually inserted and removed into posteriorincision 46 or 46′, each individual tunnel may be provided with aposterior lip similar to posterior lip 128 illustrated in FIG. 14. Inyet another exemplary embodiment, no posterior retractor is utilized.Rasping and reaming of the femur will now be described. The posteriorcapsule will be entered to facilitate rasping and reaming of the femur.Any step performed through a tubular retractor positioned in theposterior may be performed through the posterior incision without aretractor positioned therein.

[0099] Initially, under image guidance, a straight pointed awl isinserted into the posterior incision while observing its progressthrough the anterior incision. The awl is inserted into the osteotomizedfemoral neck and advanced manually down the femoral canal. Upon itsremoval, a ball tipped guide wire is inserted through the posteriorincision into the osteotomized femoral neck down the femoral canal.

[0100] Referring now to FIG. 15 in one exemplary embodiment, ball tippedguide wire 146 is inserted through guide tube 124 of posterior retractor122 and advanced into femoral canal 148. While FIG. 15 illustrates guidetube 124 nested in reamer tunnel 126 and rasp tunnel 130, guide tube 124may be directly inserted through posterior incision 46 or 46′, or notused. In one exemplary embodiment, ball-tipped guide wire 146 isdirectly inserted through posterior incision 46 or 46′ and advanced intofemoral canal 148. If the cancellous bone of femur 62 is too dense topermit insertion of ball tipped guide wire 146, then a conicalcannulated reamer or end mill is used to prepare the femoral metaphysis.If a nested posterior retractor configuration is utilized, guide tube124 must be removed so that the reamer can be inserted through reamertunnel 126 of posterior retractor 122. Similarly, if a nestedconfiguration is not utilized, reamer tunnel 126 can be inserted intoposterior incision 46 if the surgeon chooses to use it. In any event,ball tipped guide wire 146 is inserted about halfway down femoral canal148. The following detailed description of the invention makes referenceto a nested posterior retractor configuration. It will be understood bythose skilled in the art that if the nested configuration is notutilized, each individual component of posterior retractor 122 can beinserted and removed through posterior incision 46 as necessary.Moreover, if no tubular posterior retractors are utilized, then thefollowing steps can be performed by placing instruments directly throughposterior incision 46 or 46′.

[0101]FIG. 16 illustrates preparation of femoral canal 148 to receiverasp 204 (FIG. 19). Guide tube 124 is removed from posterior retractor122 and end cutter 150 (FIG. 17A) is inserted through reamer tunnel 126.FIG. 18 illustrates end cutter 150 positioned within reamer tunnel 126.End cutter 150 includes elongate aperture 160 through which guide wire146 passes and guides end cutter 150. End cutter 150 is actuated by anyof the many actuating devices known in the art. After end cutting iscomplete, end cutter 150 is removed through reamer tunnel 126 and reamer151 (FIG. 17B) is inserted therethrough. Reamer 151 includes reamerguide aperture 161 through which guide wire 146 passes and guides reamer151 as it reams femoral canal 148. Reamers of progressive increase intheir outer diameter are sequentially placed over guide wire 146 andfemoral canal 148 is reamed until cortical “chatter” is felt. As isknown in the art, the optimal diameter of femoral canal 148 isprovisionally determined by preoperative templating. Some surgeons maychoose to avoid reaming of the femoral shaft and instead utilize abroach as is known in the art. A broach may be inserted in accordancewith the current invention as described hereinbelow with respect to raspinsertion. In one exemplary embodiment, lateralizing reamers areutilized to prepare femoral canal 148.

[0102] In an alternative embodiment of the present invention, reaming offemoral canal 148 begins with the use of a flexible reamer. The flexiblereamer is used to enlarge the femoral canal along its normal axis. Inone exemplary embodiment, a cannulated flexible is utilized. In thisembodiment, the flexible reamer is positioned over the inserted ball tipguide wire. After reaming with the flexible reamer, lateralizing reamer480 is inserted through posterior incision 46 and into the femoralcanal. Lateralizing reamer 480 is a blunt tipped side cutting reamer.Lateralizing reamer 480 is utilized to remove bone stock into thegreater trochanter so that the implanted femoral stem will be coaxialwith the shaft of femur 62 and will not be aligned in varus. Statedanother way, lateralizing reamer 480 is used to side cut the femoralcanal to move the top of the pathway posteriorward allow for properimplantation of the prosthetic femoral component. If a taper fit stem isutilized, then reaming is complete after using the lateralizing reamer.If a fully coated porous stem is utilized, then a straight solid reamersuch as the VERSYS reamer available from Zimmer, Inc. is utilized tocontinue reaming the femoral canal. In all of the reaming stepsdiscussed above, a number of reamers of increasing size can be utilized.For example, when using a flexible reamer, a first flexible reamer canbe utilized to ream out the femoral canal, followed by a second flexiblereamer larger in size than the first flexible reamer.

[0103] After the correct diameter of femoral canal 148 is reamed out,reamer tunnel 126 (FIG. 14) is removed from posterior retractor 122 sothat rasp 204 and rasp handle 212 (FIG. 19) can be inserted over guidewire 146 to complete preparation of femur 62. Guide wire 146 is insertedinto rasp guide aperture 214 and rasp handle guide aperture 202 to guiderasp 204 to prepared femur 62. Impact surface 164 is struck, as is knownin the art, to place rasp 204 in femur 62. While rasp 204 is beingimpacted, the rotational alignment can be assessed by direct visualscrutiny of femur 62 through anterior incision 44. Furthermore,assessment of the alignment of rasp handle 212 with respect to thepatella, lower leg, and foot facilitates alignment. On the normalproximal femoral metaphysis, a flattened area of anterior bone providesa highly reproducable landmark for the rotational alignment. This maynot be true if the patient has experienced prior surgery or trauma.

[0104] Progressively larger rasps are inserted to achieve the optimalfit and fill in femur 62. Once the final rasp is fully seated, rasphandle 212 is removed along with guide wire 146 and posterior retractor122, leaving distal end 208 of flexible cable 192 (FIG. 19A) attached tothe proximal end of rasp 204 and proximal end 194 of flexible cable 192protruding from posterior incision 46. The operation of rasp handle 212will be further explained below. In an alternative embodiment, rasphandle 300 illustrated in FIGS. 31-36 is utilized. Rasp handle 300 canbe utilized with a VERSYS rasp available from Zimmer, Inc. The operationof rasp handle 300 and its cooperation with a femoral rasp will befurther described hereinbelow. One or more fluoroscopic images can beutilized to ensure proper orientation and position of the femoral rasps.

[0105] After the final rasp is seated in femoral canal 148, a trialacetabular liner is placed through anterior incision 44 or 44′ and intothe seated acetabular cup with the use of a liner inserter as is knownin the art. In an alternative embodiment, a trial or final acetabularliner can be seated in the seated acetabular cup prior to preparation offemur 62. Provisional neck 222 (FIGS. 23, and 24A-C) is inserted throughanterior incision 44 and locked to the top end of the seated rasp, asillustrated in FIG. 22. A trial femoral head is placed on the Morsetaper of provisional neck 222 through anterior incision 44. The hipjoint is reduced for an assessment of stability of the hip joint andlimb length. Where necessary, a second assessment is made. Once thetrial reduction is satisfactorily completed, the hip is dislocated andthe provisional head and provisional neck 222 are removed. Rasp handle212 is reinserted through posterior incision 46 over the free end offlexible cable 192. Rasp handle 212 is advanced until it can be lockedwith the seated rasp so that impact surface 164 can be impacted and theentire tool (i.e., rasp 204 and rasp handle 212) can be removed. Thetrial acetabular liner is removed through anterior incision 44. In analternative embodiment, a trial reduction can be performed utilizing thefinal femoral implant and a trial femoral head. In one exemplaryembodiment, a trial femoral head such as the one disclosed in U.S.patent application Ser. No. 09/992,639 filed Nov. 6, 2001 and publishedas U.S. Publication No. US2002/0099447 A1, the disclosure of which ishereby explicitly incorporated by reference herein.

[0106] Via anterior incision 44, the final acetabular liner 252 (FIG.30) is seated into acetabular cup 250 (FIG. 30) with a liner inserterthat permits its impaction in place, as is known in the art. Femoralimplant 238 (FIG. 30) is anchored to femoral stem insertion tool 240(FIG. 29) and placed through posterior incision 46 or 46′. Femoralimplant 238 can be, e.g., a VERSYS fiber metal taper, a VERSYS fibermetal midcoat, or a VERSYS full coat stem available from Zimmer, Inc. Asillustrated in FIG. 25, femoral implant 238 is placed in protective,disposable bag 242 prior to its introduction into posterior incision 46or 46′. Protective, disposable bag 242 keeps femoral implant 238 cleanas it is inserted through posterior incision 46. Note that FIG. 25illustrates femoral implant 238 oriented as it will be when placed infemur 62. To insert femoral implant 238 through posterior incision 46,femoral implant 238 can be rotated 180° from this position to preventimpingement on the body. Femoral implant 238 is then rotated 180° afterbeing completely inserted through posterior incision 46. Similarrotations of femoral implant 238 can be made when utilizing posteriorincision 46′.

[0107]FIG. 26 illustrates femoral stem 238 and bag 242 inserted throughposterior incision 46. When the tip of femoral stem 238 approaches theosteotomized femoral neck, the distal end of bag 242 is incised asillustrated in FIG. 27. Scalpel 246 is inserted into anterior incision44 to incise bag 242. As femoral stem 238 is driven into femoral canal148, bag 242 is progressively removed through posterior incision 46 asillustrated in FIG. 28. After femoral stem 238 is fully seated, femoralstem insertion tool 240 (FIG. 29) is removed through posterior incision46. Through anterior incision 44, the final femoral head is positionedon the femoral neck Morse taper using a standard holding device andsecured with a standard impaction tool and mallet. The hip is thenreduced and assessed for stability. While described with reference toanterior incision 44 and posterior incision 46, this method of seatingfemoral stem 238 is equally applicable when using anterior incision 44′and posterior incision 46′.

[0108] After appropriate antibiotic irrigation and pulsatile lavage, thehip capsule and the soft tissues are repaired with heavy sutures orstaples. A suitable local anesthetic solution is injected into theclosed hip joint as well as the capsular layer and the subcutaneoustissues, allowing superior postoperative pain relief. The fasciallayers, subcutaneous tissues, and skin of both the anterior andposterior wounds are closed in a conventional method and dressings areapplied. A suction drain may be used at the discretion of the surgeon.

[0109] Osteotomy guide 78, illustrated in use in FIG. 4, includes handle80, alignment portion 82, and cut guide 84. In one exemplary embodiment,cut guide 84 and alignment portion 82 form a 60° angle. In one exemplaryembodiment, alignment portion 82 includes a tapered distal end asillustrated in FIGS. 5A and 5B. Osteotomy guide 78 is inserted throughanterior incision 44 and is positioned with alignment portion 82 placedon femur 62 so that alignment portion 82 generally aligns with thelongitudinal axis of femur 62. Handle 80 protrudes through anteriorincision 44 and may be utilized to position osteotomy guide 78. Afterosteotomy guide 78 is properly positioned, cut guide 84 is utilized tomark cut line 85 on femoral neck 60 as illustrated in FIG. 4. Osteotomyguide 78 can be formed to function on either side of the body. FIG. 4illustrates an osteotomy guide designed to function on the right femur,while FIG. 5B illustrates an osteotomy guide operable to function on theleft femur.

[0110] FIGS. 37-45 illustrate cup inserter 360 of the present invention.Cup inserter 360 is particularly advantageous when performing theminimally invasive total hip arthroplasty of the present invention duein part to the offset of offset frame leg 376 from the remainder offrame 368. This offset advantageously allows for placement of anacetabular cup in the correct anteversion and abduction withoutinterference from soft tissue. Referring to FIG. 37, acetabular cupinserter 360 includes frame 368 having handle 350 secured to a proximalend thereof. Handle 350 includes impaction surface 352 useful inimpacting an acetabular cup such as a press fit or spiked acetabularcup. Distal end 370 of frame 360 is adapted for connection of theacetabular cup thereto as will be further described hereinbelow.

[0111] Referring to FIGS. 37 and 38, drive shaft 378 of cup inserter 360is rotated via drive shaft handle 382, or torque handle 432 if it isprovided. Rotation of drive shaft 378 operates to rotate threaded distalend 394 of threaded shaft 392 to secure or release an acetabular cup tocup inserter 360 as will be further described hereinbelow. Drive shafthandle 382 may include a ratchet mechanism and may further include aclutch to limit applied torque so that the acetabular cup is not securedtoo tightly to cup inserter 360. As illustrated in FIG. 38, acetabularcup inserter 360 includes threaded shaft 392 having threaded distal end394 protruding from the distal end of acetabular cup inserter 360.Threaded distal end 394 of threaded shaft 392 is threaded into athreaded central aperture of an acetabular cup to secure the acetabularcup to cup inserter 360. After seating of the acetabular cup, threadedshaft 392 is rotated to release the acetabular cup from engagement withcup inserter 360. To secure or release an acetabular cup to cup inserter360, torque is applied to drive shaft 378 through one or both of driveshaft handle 382 and torque handle 432. As illustrated in FIGS. 37 and38, drive shaft 378 is positioned through drive shaft aperture 388formed in frame 368 of cup inserter 360. Drive shaft 378 includes driveshaft retaining groove 386 into which drive shaft retaining pin 384 ispositioned as illustrated in FIG. 38 to prohibit axial displacement ofdrive shaft 378. In assembly, distal end 380 of drive shaft 378 ispositioned within proximal end 358 of connecting shaft 354 asillustrated in FIG. 38. In assembly, connecting shaft 354 occupiesconnecting shaft aperture 426 (FIG. 39) of frame 368. As illustrated inFIG. 39, connecting shaft aperture 426 includes a counterbore formingshoulder 428. Proximal end 358 of connecting shaft 354 similarlyincludes shoulder 416 as illustrated in FIG. 37. In construction,shoulder 416 of connecting shaft 354 abuts shoulder 428 of connectingshaft aperture 426 to limit axial displacement of connecting shaft 354relative to frame 368 of acetabular cup inserter 360.

[0112] As illustrated in FIG. 38, distal end 380 of drive shaft 378 ispositioned within proximal end 358 of connecting shaft 354. Distal end380 of drive shaft 378 is identical to distal end 356 of connectingshaft 354 illustrated in detail in FIGS. 42-45 and further describedhereinbelow. In assembly, threaded shaft 392 is positioned withinthreaded shaft aperture 422 (FIG. 39) of frame 368. As illustrated inFIG. 39, threaded shaft aperture 422 includes a counterbore formingshoulder 424. Similarly, proximal end 396 of threaded shaft 392 includesshoulder 418. In construction, spring 398 (FIG. 37) is, in one exemplaryembodiment, positioned about threaded shaft 392, intermediate shoulder418 of threaded shaft 392, and shoulder 424 of threaded shaft aperture422. As illustrated in FIG. 38, distal end 356 of connecting shaft 354is positioned within proximal end 396 of threaded shaft 392. Distal end380 of drive shaft 378 and proximal end 358 of connecting shaft 354cooperate to form a universal joint. Similarly, distal end 356 ofconnecting shaft 354 and proximal end 396 of threaded shaft 392cooperate to form a universal joint.

[0113] As described supra, distal end 380 of drive shaft 378 issubstantially identical to distal end 356 of connecting shaft 354.Similarly, proximal end 358 of connecting shaft 354 is substantiallyidentical to proximal end 396 of threaded shaft 392. The structure ofthe universal joint formed by distal end 356 of connecting shaft 354 andproximal end 396 of threaded shaft 392 will now be described in detail.The structure and function of the universal joint formed by distal end380 of drive shaft 378 and proximal end 358 of connecting shaft 354 isidentical to the universal joint formed by distal end 356 of connectingshaft 354 and proximal end 396 of threaded shaft 392 and will not bedescribed in detail for the sake of brevity.

[0114] As illustrated in FIGS. 40 and 41, proximal end 396 of threadedshaft 392 includes drive aperture 434 having a hexagonal cross sectionas illustrated in FIG. 41. Similarly, distal end 356 of connecting shaft354 has a hexagonal cross section as illustrated in FIG. 45A. Asillustrated in FIGS. 37 and 42, distal end 356 of connecting shaft 354comprises a six sided spheroid. Taking distal most point 357 (FIG. 37)of distal end 356 as a pole of the spheroid, an opposing, imaginary poleis positioned within connecting shaft 354. To form the six sidedspheroid of distal ends 356 and 380 of connecting shaft 354 and driveshaft 378, a sphere can be machined such that a straight edged toolintersecting a first pole, e.g., distal most point 357, and positionedperpendicular to a primary axis formed by distal most point 357 and theopposing imaginary pole, can be moved from distal most point 357 towardthe opposing imaginary pole while maintaining the straight cutting edgeof this instrument perpendicular to the primary axis. This procedure canbe repeated at six evenly spaced intervals about the periphery of thesphere to form the six sided spheroid of distal ends 356 and 380.

[0115] As illustrated in FIG. 38, distal end 380 of drive shaft 378 ispositioned within proximal end 358 of connecting shaft 354 such thatconnecting shaft 354 and drive shaft 378 are not colinear. FIG. 45Billustrates a section of distal end 356 (which is identical to distalend 380) taken along a line transverse to proximal end 358 of connectingshaft 354 when connecting shaft 354 is assembled in cup inserter 360 asillustrated in FIG. 38. As illustrated in FIG. 45B, the spheroidal shapeof the male aspect of the universal joints of the present invention willprovide linear contact surfaces for the hexagonal sides of the femaleaspect of the universal joint of the present invention when the femaleaspect is angled relative to the male aspect. In this way, torque can betransmitted from the male aspect of a universal joint of the presentinvention to a female aspect in a nonlinear fashion.

[0116] The universal joints of cup inserter 360 allow for transmissionof torque applied to one or both of drive shaft handle 382 and torquehandle 432 through drive shaft 378, connecting shaft 354, and threadedshaft 392. Therefore, rotation of drive shaft handle 382 and/or torquehandle 432 will rotate threaded distal end 394 of threaded shaft 392 tosecure an acetabular cup to acetabular cup inserter 360, or to allow fordetachment of an acetabular cup from acetabular cup inserter 360. Whensecuring an acetabular cup to acetabular cup inserter 360, threadeddistal end 394 of threaded shaft 392 is rotated relative to theacetabular cup to engage the acetabular cup thereto. As the acetabularcup is secured to acetabular cup inserter 360, threaded shaft 392 may bedrawn distally through threaded shaft aperture 422 (FIG. 39) to allowfor additional exposure of threaded distal end 394 and provide forsecure engagement of an acetabular cup to acetabular cup inserter 360.When this occurs, threaded shaft 392 acts against the biasing force ofspring 398. This extension aspect of threaded shaft 392 is particularlyadvantageous when using a relatively small acetabular cup, whichrequires additional threads for engagement therewith, relative to alarger acetabular cup.

[0117] As illustrated in FIGS. 37 and 39, distal end 370 of acetabularcup inserter 360 includes C-ring groove 374. In construction, C-ringgroove 374 accommodates C-ring 372 (FIG. 37). With C-ring 372 positionedabout C-ring groove 374, end cap 414 can be positioned about distal end370 of acetabular cup inserter 360 and locked in place, with C-ring 372acting to create an interference fit with end cap 414. When anacetabular cup is secured to acetabular cup inserter 360, threaded shaft392 draws the interior of the acetabular cup into locked engagement withend cap 414, forcing the proximal end of end cap 414 into secureengagement with frame 368 of acetabular cup inserter 360. Therefore,impaction force applied to impaction surface 352 will be transmittedthrough frame 368 to the acetabular cup. Impaction force will not betransmitted through the universal joint linkage described hereinabove.In one exemplary embodiment, end cap 414 is made of polyethylene.

[0118]FIG. 46 illustrates alternative embodiment acetabular cup inserter360′. Acetabular cup inserter 360′ shares many similar components withacetabular cup inserter 360. Components of acetabular cup inserter 360′which are identical or significantly similar to corresponding componentsof acetabular cup inserter 360 are designated with primed referencenumerals. Acetabular cup inserter 360′ utilizes a universal jointlinkage to transmit torque applied to drive shaft handle 382′ tothreaded shaft 438. The universal joints of acetabular cup inserter 360′differ from those described above with respect to acetabular cupinserter 360 in that they are pinned universal joints. Because pinneduniversal joints are utilized with acetabular cup inserter 360′, U-jointlinkage 448 is provided. U-joint linkage 448 is secured via U-joint pin450 to distal end 356′ of connecting shaft 354′. U-joint linkage 448includes groove 446 into which tab 444 of threaded shaft 438 ispositioned to allow for torque transmission to threaded shaft 438. Tab444 and groove 446 are sized to allow for maximum extension of threadedshaft 438 from frame 368′ as described hereinabove with respect toacetabular cup inserter 360. Threaded shaft 438 and U-joint linkage 448are illustrated in detail in FIGS. 47-50.

[0119] Acetabular cup inserter 360′ includes a locking mechanism forrestricting rotational movement of drive shaft 378′. Locking lever 452and locking shaft 454 are illustrated in FIG. 46 and cooperate withlifter 462 to create an interference fit between drive shaft 378′ andframe 368′ to prohibit rotational movement of drive shaft 378′. Lockinglever 452 and locking shaft 454 are illustrated in detail in FIGS.51-55. As illustrated in FIG. 51, locking lever 452 includes partialcylindrical wall 464 having locking tab aperture 456 formed therein.Locking shaft 454 includes locking tab 458 formed on distal end 466thereof. In assembly, distal end 466 of locking shaft 454 is positionedwithin partial cylindrical wall 464 of locking lever 452, with lockingtab 458 positioned within locking tab aperture 456 to prohibit relativerotational movement of locking lever 452 and locking shaft 454. Asillustrated in FIGS. 53-55, locking shaft 454 includes cam 460. Inassembly, cam 460 is aligned with lifter aperture 470 (FIG. 46) of frame368′. Lifter 462 is positioned within lifter aperture 470 atop lockingshaft 454. Locking lever 452 includes tab 468 against which force can beapplied to rotate locking shaft 454. Specifically, locking shaft 454 canbe rotated until cam 460 does not contact lifter 462 to allow forrotation of drive shaft 378′. Similarly, locking shaft 454 may berotated until cam 460 forces lifter 462 into frictional engagement withdrive shaft 378′ to prohibit rotational movement thereof. When lockinglever 452 is rotated to lock drive shaft 378, lifter 462 is forced intoengagement with drive shaft 378′ and drive shaft 378′ is forced intoengagement with the interior wall of drive shaft aperture 388′ tofrictionally lock drive shaft 378′. The locking mechanism described withrespect to acetabular cup inserter 360′ may be applied to acetabular cupinserter 360 as well. This locking mechanism is advantageous because itwill prohibit relative rotation between an acetabular cup secured toacetabular cup inserter 360′, and acetabular cup inserter 360′.

[0120] After locking an acetabular cup to acetabular cup inserter 360′,drive shaft handle 382 may be rotated to rotate the acetabular cuprelative to acetabular cup inserter 360′. This feature allows forplacement of the acetabular cup locking mechanism in a desirablelocation to allow for revision surgery. Once the desired orientation ofthe acetabular cup is achieved, the locking mechanism may be utilized toprohibit further relative rotation of the acetabular cup relative toacetabular cup inserter 360′ as described above. While both acetabularcup inserter 360 and acetabtilar cup inserter 360′ have been describedas utilizing a pair of universal joints to transmit torque along anonlinear path, both acetabular cup inserter 360 and 360′ may utilize aflexible shaft to transmit torque from drive handle 382, 382′ tothreaded shaft 392, 438, respectively.

[0121]FIG. 9B illustrates use of acetabular cup inserter 360. Toproperly align acetabular cup inserter 360 for optimum placement of anacetabular cup, A-frame 472 is secured via set screw 476 to alignmentframe post 390. With A-frame 472 secured to acetabular cup inserter 360,A-frame 472 is positioned parallel to a coronal plane, as illustrated inFIG. 9B, with one A-frame leg 474 parallel to a sagittal plane and oneA-frame leg 474 perpendicular to a sagittal plane. With A-frame 472positioned in this way, the optimum orientation of the acetabular cup isachieved. In one exemplary embodiment, proper alignment of A-frame 472,as described above, leads to an acetabular cup orientation having 20° ofanteversion and 45° of abduction. In an alternative embodiment, an imageguidance array can be secured to alignment frame post 390 to allow forcomputer assisted guidance of acetabular cup inserter 360. Inalternative embodiments, cup inserters 360, 360′ are utilized with apatient in an alternative position, such as, e.g., a lateral position.In these embodiments, different reference frames having different pointsof reference can be utilized.

[0122] As discussed supra, awl 106 (FIG. 12) is designed for insertionthrough anterior incision 44 or 44′ to locate posterior incision 46 or46′. Awl shaft 116 includes proximal end 110 designed for insertion intohandle 112. Handle 112 includes a longitudinal channel 120 into whichproximal end 110 of awl shaft 116 may be inserted. Locking screw 118 isoperably positioned in handle 112 and may be actuated by locking knob114. Locking knob 114 is utilized to place locking screw 118 in lockingengagement with proximal end 110 of awl 106. In one exemplaryembodiment, proximal end 110 of awl 106 includes a flat portion toengage locking screw 118 and facilitate the locking engagement of awlshaft 116 to handle 112. Awl shaft 116 further includes distal end 108.Distal end 108 is generally straight and is utilized to generally alignwith a longitudinal axis of femur 62 (FIG. 11). As illustrated in FIG.12, distal end 108 of awl shaft 116 includes a tapered end to facilitateinsertion of awl 106 through anterior incision 44 or 44′ to locateposterior incision 46 or 46′. Additionally, distal end 108 of awl 106may be of smaller diameter than the body of awl shaft 116 as illustratedin FIG. 12. In an alternative embodiment, awl 106 is formed in one pieceand is disposable.

[0123] Referring now to FIG. 14, posterior retractor 122 comprises threenested parts. Guide tube 124 is nested in reamer tunnel 126 while reamertunnel 126 is nested in rasp tunnel 130. When posterior retractor 122 isthreaded into posterior incision 46 or 46′, guide tube 124, reamertunnel 126, and rasp tunnel 130 can be nested together to form a singleunit. Rasp tunnel 130 includes exterior threads 132 to facilitatethreading of posterior retractor 122 through posterior incision 46. Rasptunnel 130 includes rasp aperture 134 through which reamer tunnel 126may be inserted and, in one alternative embodiment, posterior lip 128for positioning posterior retractor 122, as discussed above. Reamertunnel 126 includes flange 136 which is operable to retain the positionof reamer tunnel 126 within rasp tunnel 130. Reamer tunnel 126 includesreamer aperture 138 through which guide tube 124 may be inserted. Guidetube 124 includes a tapered distal end 140 to facilitate its insertioninto reamer aperture 138. Guide tube 124 includes guide wire aperture144 through which guide wire 146 (FIG. 15) may be inserted. Reameraperture 138 is sized to allow insertion of end cutter 150 (FIG. 18), orfemoral reamer 151 as discussed above. As illustrated in FIG. 18, guidetube 124 is removed from reamer tunnel 126 and end cutter 150 isinserted through reamer aperture 138. Longitudinal reamer aperture 138is sized to accommodate guide cylinders 156 and to thereby provideguidance and stability to end cutter 150. After end cutting (andreaming, if desired) is complete, reamer tunnel 126 is removed from rasptunnel 130. Rasp aperture 134 is sized to accommodate insertion of rasp204 as well as cannular insertion member 168 of rasp handle 212. Forsurgeries which do not utilize reaming, the posterior retractor cancomprise a rasp tunnel with a guide tube nested therein and not includea reamer tunnel as described above. As described above, posteriorretractor 122 is not always utilized, and if utilized, is not alwaysutilized in its nested configuration. In one exemplary embodiment, guidetube 124, reamer tunnel 126, and rasp tunnel 130 are each inserted intoand removed from posterior incision 46 as necessary. In an alternativeembodiment, the tubular retractor disclosed in U.S. patent applicationSer. No. 09/992,639 filed Nov. 6, 2001 and published as U.S. PublicationNo. US2002/0099447 A1, the disclosure of which is hereby explicitlyincorporated by reference herein, is utilized.

[0124] Referring now to FIG. 21, rasp handle 212 includes cannularinsertion member 168, impact surface 164, grip 166, elongate guideaperture 202, elongate aperture 200, and engagement channel 190. Rasp204 includes an aperture 216 sized to receive and retain retainer 210 ondistal end 208 of flexible cable 192. Retainer 210 is placed in aperture216 and flexible cable 192 follows cable channel 217 to exit rasp 204.Proximal end 194 of flexible cable 192 is inserted through elongateaperture 200 of cannular insertion member 168 and distal rasp engagementguide 206 is piloted to guide channel 215 of rasp 204. After exiting theproximal end of elongate aperture 200, proximal end 194 of flexiblecable 192 may be received in engagement channel 190. Engagement channel190 is sized to accommodate and retain retainer 196. After retainer 196is operably positioned in engagement channel 190, grip 166 may beactuated to tension flexible cable 192.

[0125] Referring now to FIG. 20B, retainer 196 is operably positioned inengagement channel 190. Attaching means 184, such as, e.g., rivets,belts, etc. are utilized to affix biasing elements 172 to grip 166 andinternal handle surface 182. Grip 166 is outwardly biased by handlebiasing elements 172 and pivots about pivot point 198. Grip 166 includestensioning member 188 and ratchet 174. Ratchet 174 is designed forengagement with tapered end 186 of pawl 176. Pawl 176 includes pawlflange 178. Spring 180 engages internal handle surface 82 and pawlflange 178 to bias pawl 176 toward cannular insertion member 168.Actuation of grip 166 against the biasing force of biasing elements 172rotates grip 166 about pivot point 198, causes ratchet 174 to come intooperative engagement with tapered end 186 of pawl 176, and causestensioning member 188 to contact flexible cable 192. FIG. 20Aillustrates grip 166 retained by pawl 176 in the closed position. Asillustrated, tensioning member 188 contacts and tensions flexible cable192, thus locking rasp 204 to rasp handle 212. Lock disengagement knob170 can be pulled against the biasing force of spring 180 to unlock grip166.

[0126] FIGS. 31-36 illustrate an alternative embodiment rasp handle inaccordance with the present invention. As illustrated in FIGS. 31-35,rasp handle 300 includes proximal end 302 including impaction surface328 (see, e.g., FIGS. 32-35). Proximal end 302 further includes aplurality of guide handle apertures 316 into which anteversion handle312 (FIGS. 31 and 33) can be secured. When using rasp handle 300 to seata rasp in femur 62, anteversion handle 312 can be utilized to set theanteversion of the femoral implant. As illustrated in FIG. 36, proximalend 302 of rasp handle 300 includes three anteversion handle apertureson each side thereof. Specifically, anteversion holes 316 a′, 316 b′,and 316 c′ are left anteversion holes, while anteversion holes 316 a,316 b, and 316 c are right anteversion holes. That is, anteversion holes316 a′, 316 b′, and 316 c′ are utilized to set femoral implantanteversion when performing a total hip arthroplasty on the left hip,while anteversion holes 316 a, 316 b, and 316 c are utilized to setanteversion of the femoral implant when performing a total hiparthroplasty of the right hip. Anteversion holes 316 a and 316 a′ areset at 0° of anteversion. Anteversion holes 316 a and 316 a′ areutilized when no anteversion of the femoral implant is sought. In suchan embodiment, anteversion handle 312 is connected to the appropriateanteversion aperture 316 a or 316 a′ and vertically positioned (with thepatient lying in a supine position) to prepare femur 62 to receive afemoral implant in 0° of anteversion. Anteversion apertures 316 b and316 b′ form an angle of 7½ degrees with anteversion apertures 316 a and316 a′, respectively. These apertures can be utilized to set 7½ degreesof anteversion for the femoral implant. Similarly, anteversion apertures316 c and 316 c′ form an angle of 15° with anteversion apertures 316 aand 316 a′ and can be used to set anteversion of 15° for the femoralimplant. For the purposes of this document, when referring to the angleformed by a pair of anteversion apertures, the longitudinal axis of eachaperture forms a line comprising a leg of the referenced angle. If asurgeon wants to achieve 7½ or 15 degrees of anteversion, the surgeoncan insert anteversion handle 312 into the appropriate anteversionaperture and orient anteversion handle 312 vertically to achieve thedesired anteversion. Proximal end 302 of rasp handle 300 furtherincludes slap hammer aperture 344 for connection of a slap hammer torasp handle 300. Slap hammer aperture 344 is provided in the event thata surgeon does not favor rasp removal by means of impacting theundersurface of proximal end 302, i.e., the surface opposite impactionsurface 328.

[0127] As illustrated in FIGS. 31, 32, and 34, rasp handle 300 includesframe 314 having transverse apertures 322 formed therein. Transverseapertures add to the cleanability of rasp handle 300 and provide forweight reduction over an embodiment absent transverse apertures 322.

[0128] To secure rasp 204′ (FIG. 35) to rasp handle 300, handle lever304 is rotated away from frame 314 to the position illustrated in FIG.35. Rotation of handle lever 304 to this position effects proximalmovement of second handle lever pin 334 which, consequently, moveslinkage arm 308 and linkage arm pin 336 proximally. Locking jaw 306 ispivotally secured to frame 314 via locking jaw pin 338 so that movementof handle lever 304 causes rotation of locking jaw 306 about locking jawpin 338 and positions locking jaw 306 as illustrated in FIG. 35. Asillustrated in FIGS. 31 and 32, handle lever 304 is pivotally connectedto frame 314 via first handle lever pin 330. First handle lever pin 330is positioned in channel 332 formed in frame 314. Placement of firsthandle lever pin 330 in channel 332 allows for proximal/distaltranslation of handle lever 304. As illustrated in FIGS. 34 and 35,handle lever 304 is pivotally connected to linkage arm 308 via secondhandle lever pin 334. Linkage arm 308 is pivotally connected via linkagearm pin 336 to locking jaw 306 and locking jaw 306 is pivotallyconnected to frame 314 via locking jaw pin 338. As illustrated in FIG.32, frame 314 includes locking jaw pin aperture 340 into which lockingjaw pin 338 is positioned.

[0129] To secure rasp 204′ to rasp handle 300, post 318 of rasp 204′ isinserted into rasp handle docking aperture 326 and docking boss 324 ofrasp handle 300 is positioned in rasp handle docking aperture 346 ofrasp 204′. Handle lever 304 is then rotated from the positionillustrated in FIG. 35 to the position illustrated in FIG. 34. Rotationof handle lever 304 to the position illustrated in FIG. 34 causesmovement of second handle lever pin 334 from the position illustrated inFIG. 35 to the position illustrated in FIG. 34 and consequently causesdistal movement of linkage arm 308, and linkage arm pin 336 which causesrotation of locking jaw 306 into the position illustrated in FIG. 34,with locking tooth 342 of locking jaw 306 postioned within V-notch 320of post 318 of rasp 204′. If insufficient clamping force is exerted onV-notch 320 of post 318 by locking jaw 306, then handle lever 304 can bemoved into the open position illustrated in FIG. 35 and adjustment screw310 can be utilized to displace first handle lever pin 330 distally sothat actuation of handle lever 304 into the closed position will causegreater distal displacement of linkage arm 308 and linkage arm pin 336,and, consequently, cause greater rotation of locking jaw 306 to exertadditional clamping force on post 318 of rasp 204′

[0130] After the final rasp is fully seated in femur 62 as describedhereinabove, handle lever 304 can be rotated into the open positionillustrated in FIG. 35 to allow for disengagement of rasp handle 300from rasp 204′ so that a trial reduction can be performed with a trialfemoral neck and head secured to rasp 204′. After completion of a trialreduction, rasp handle 300 is reinserted into the body and docked withrasp 204 to allow for removal thereof. To redock rasp handle 300,tactile feedback is utilized to identify post 318 of rasp 204′. After itis located, post 318 is positioned within rasp handle docking aperture326 which is facilitated by the fact that rasp handle docking aperture326 includes a female taper whereby the distal most portion of rasphandle docking aperture 326 is larger than the proximalmost portionthereof. With post 318 positioned within rasp handle docking aperture326, rotation of rasp handle 300 can be utilized to position dockingboss 324 in rasp docking aperture 346. Handle lever 304 is then rotatedfrom the open position illustrated in FIG. 35 to the closed positionillustrated in FIG. 34 to secure rasp 204′ to rasp handle 300. In theevent that the proximal end of rasp 204′ does not abut the distal end ofrasp handle 300, the cooperating ramped surfaces of locking tooth 342and V-notch 320 will work to draw rasp handle 300 closer to rasp 204until they are positioned in abutting relationship. As illustrated inFIGS. 31, 32, and 35, rasp handle docking aperture 326 includes radiusedprofile 348 which allows for escape of soft tissues from between rasphandle 300 and rasp 204′ when rasp handle 300 is secured to rasp 204′.With rasp handle 300 secured to rasp 204′, rasp 204′ can be removed fromfemur 62 to allow for seating of the final femoral implant. In analternative embodiment, an image guidance array can be utilized in lieuof or in addition to anteversion handle 312 to position rasp 204 in theappropriate orientation in the femur. The rasp handles of the presentinvention are advantageously formed with a low profile insertion memberheading a cross sectional area no greater than the rasps to which theyare attached.

[0131] Referring now to FIG. 23, provisional neck 222 can be locked torasp 204 utilizing forceps 220. Forceps 220 include blade ends 230, 232.Blade ends 230, 232 are sized for insertion into provisional headapertures 234, 236, respectively (FIGS. 24B and 24C). As illustrated inFIG. 24A, provisional neck 222 includes locking cylinder 224 and spring228. Spring 228 upwardly biases locking cylinder 224. Upon insertioninto apertures 234, 236, blade ends 230, 232 can contact tapered portion226 of locking cylinder 224. Actuation of blade ends 230, 232 againsttapered portion 226 causes locking piston 224 to move in a directionopposite to the biasing force of spring 228. Provisional neck 222 isclamped to forceps 220 and slid in a radial direction into provisionalneck engagement area 218 (FIGS. 21 and 21 A) on rasp 204. Afterprovisional neck 222 is fully slid onto rasp 204, forceps 220 may bereleased, thereby allowing locking piston 224 to return to its lockedposition under the biasing force of spring 228. Rasp 204 includescircular cut outs 217 which can be engaged by locking cylinder 224 tolock provisional neck 222 in place.

[0132] Channels 225 (FIG. 24A) on provisional neck 222 accommodateprotrusions 219 (FIG. 21) on rasp 204. Provisional neck 222 is slid ontorasp 204 with protrusions 219 occupying channels 225 of provisional neck222. Stop 223 of provisional neck 222 abuts protrusions 219 whenprovisional neck 222 is completely slid onto rasp 204. When stop 223abuts protrusions 219, locking cylinder 224 may be locked (i.e., forcepblades 230, 232 released) so that locking cylinder 224 engages circularcut outs 217, locking provisional neck 222 to rasp 204.

[0133] FIGS. 56-61 illustrate operating table 400 in accordance with thepresent invention. As illustrated in FIGS. 56-58, operating table 400 issecured to base 402 via supports 404. Operating table 400 includes apair of leg panels 412 on top of which a patient's legs can bepositioned. Each leg panel 412 includes a buttocks door 406. Eachbuttocks door 406 includes a hinge 407 as illustrated in FIG. 58. Hinge407 hingedly connects medial side 409 of each buttocks door 406 to a legpanel 412 so that each buttocks door 406 can be rotated between theclosed position illustrated in FIG. 59 to support a patient's buttocks,to the open position illustrated in FIG. 60, allowing a patient'sbuttocks to protrude through the top of operating table 400. Each legpanel 412 is hingedly connected to operating table 400 and, therefore,is rotatable from the supine position illustrated in FIGS. 56, and 58-60and the hyperextended position illustrated in FIG. 61. In the exemplaryembodiment illustrated in FIGS. 56-61, each leg panel 412 includes asupport 410 useful in maintaining the leg panel in one of the supine andhyperextended positions as illustrated in FIG. 61. In furtherembodiments of operating table 400, leg panels 412 will be mechanicallyor hydraulically actuatable between a supine and hyperextended positionand include the ability to achieve nearly infinite degrees ofhyperextension from about 0° of hyperextension, i.e., supine, to about120° of hyperextension.

[0134]FIG. 59 illustrates patient 40 including operative leg 48. Asillustrated in FIG. 59, patient 40 is placed in supine position atopoperating table 400 with operative leg 48 positioned atop one of legpanels 412. The non-operative leg is similarly placed atop the remainingleg panel 412. With the patient positioned as illustrated in FIG. 59,buttocks door 406 can be rotated into the open position illustrated inFIG. 60 to allow buttocks 50 to protrude through the top of operatingtable 400. As illustrated in FIG. 61, leg panel 412 positionedunderneath operative leg 48 can be rotated to position operative leg 48in approximately 90° of hyperextension. Buttocks door 406 advantageouslyallows the operative leg of a larger patient to be placed in a greaterdegree of hyperextension than would be allowable without buttocks door406.

[0135] The top surface of operating table 400 is completely radiolucentto allow for intraoperative image intensification. Furthermore,operating table 400 is constructed to be of minimal width to carry anaverage size patient thereon to allow for maximum ease of use of a C-armimage intensification system. In one exemplary embodiment, a system ofoperating tables 400 is provided, each with increasing width toaccommodate patients of varying size while providing a table of minimumwidth to support the relevant patient. The relatively narrow width ofoperating table 400 is advantageous in that the operating surgeon willstand adjacent operative leg 48 while the C-arm image intensificationsystem will be positioned adjacent the opposite side of operating table400. The relatively narrow width of operating table 400 will thereforeallow for optimum placement of the C-arm image intensification systemwith respect to operative leg 48. It is important to note that support410 associated with each leg panel 412 will be sized to accommodatepassage of a C-arm thereabout and will be formed of radiotransparentmaterial. Operating table 400 is useful when hyperextending thenon-operative leg as described hereinabove. Furthermore, operating table400 is useful in performing the one incision minimally invasive totalhip arthroplasty described hereinbelow because the non-operative leg canbe hyperextended as described hereinabove.

[0136] The present invention provides for a single incision minimallyinvasive total hip arthroplasty. The total hip arthroplasty of this formof the present invention is prepared utilizing one of anterior incisions44 and 44′. In the total hip arthroplasty of this form of the presentinvention, the acetabulum is prepared and the acetabular component isseated as is discussed above with respect to the two incision minimallyinvasive total hip arthroplasty. In this form of the present invention,the operative leg is hyperextended at least about 70° and the femur isprepared and the femoral implant is seated through the anteriorincision. In one exemplary embodiment of the one incision minimallyinvasive total hip arthroplasty of the present invention, the leg ishyperextended about 75° to 90°.

[0137]FIG. 61 illustrates patient 40 with operative leg 48 hyperextendedto about 90° of hyperextension. Use of operating table 400 of thepresent invention to allow for this hyperextension of operative leg 48is described hereinabove. After operative leg 48 is positioned asillustrated in FIG. 61, retractors are inserted into the anteriorincision and positioned around the upper femur to allow forvisualization of the bone. Advantageously, as operative leg 48 ishyperextended, the proximal femur is positioned closer to the anteriorincision to allow for visualization of the osteotomized femoral neckthrough the anterior incision. This arrangement is clearly depicted inthe supine elevational view of FIG. 62 in which osteotomized femoralneck 478 is clearly visible through the anterior incision. Afterpositioning operative leg 48 as illustrated in FIGS. 61 and 62,preparation of the femur begins. The technique used for preparing femur62 (FIG. 62) will depend in large part on patient physiology.Specifically, the technique described above with respect to the twoincision minimally invasive total hip arthroplasty can be used toprepare femur 62 is patient physiology allows for hyperextension toabout 90° to allow for maximum access to osteotomized femoral neck 478.If patient physiology allows for hyperextension to only about 75° to80°, then an alternative technique may be utilized to prepare femur 62to receive the femoral implant. Specifically, in this latter case wherehyperextension of only about 75° to 80° is possible, curved instrumentsmay be utilized to prepare femur 62 to receive a curved femoral implant.

[0138] If the operative hip cannot be hyperextended to about 90° then,generally speaking, direct access to osteotomized femoral neck 478(FIG.62) cannot be achieved. With this in mind, straight instruments forpreparing femur 62 to receive a femoral implant will generally not beapplicable because such instruments typically require insertion directlyinto osteotomized femoral neck 478 coaxial with the principal portion ofthe femoral shaft. In this situation, curved preparation tools can beutilized because such tools can be inserted into the osteotomizedfemoral neck along the axis of the posterior femoral bow.

[0139] Preparation of the femur in a case in which about 90° ofhyperextension cannot be achieved can begin by inserting a curved awlinto osteotomized femoral neck 478. The curved awl will follow theposterior bow of the femur and begin preparation of the intramedullarycanal of femur 62 to receive a femoral implant. In one exemplaryembodiment, a curved rasp is utilized to begin preparation of thefemoral canal. If reaming is desired, a flexible reamer can be insertedinto the intramedullary canal of the femur to ream the same. Theflexible reamer will generally glance off the posterior cortical wall offemur 62 and effect reaming of the intramedullary canal. A guide wiremay or may not be utilized with the flexible reamer. After inserting theawl and reaming as necessary, a curved femoral rasp is used to completepreparation of the femur to receive, e.g., a curved prosthetic femoralcomponent. The curved femoral rasp can be utilized to effect a trialreduction as described hereinabove with respect to the two incisionminimally invasive total hip arthroplasty. To perform a trial reduction,operating table 400 will be returned to the position illustrated in FIG.60 to return patient 40 to the supine position. Patient leg 48 againwill be hyperextended as illustrated in FIGS. 61 and 62 to allow forremoval of the final femoral rasp and seating of the femoral implant.

[0140] While the method of the current invention has been described withreference to particular hip prostheses, this is not meant to be limitingin any way and it will be understood that the method of the currentinvention could be used with many prosthetics, including, e.g., acementless prosthesis, a hybrid prosthesis having a cemented stem and acementless acetabular cup, a cemented prosthesis having both a cementedstem and a cemented acetabular cup, or an Endo prosthesis for replacingonly the femoral head. In a procedure in which a cemented femoral stemis utilized, the bone cement will generally be inserted through theanterior incision and a bagged stem will be inserted through theposterior incision. If the single anterior incision is utilized, acemented stem could be inserted without requiring use of the protectivebag described above.

[0141] While this invention has been described as having a preferreddesign, the present invention can be further modified within the spiritand scope of this disclosure. This application is therefore intended tocover any variations, uses, or adaptations of the invention using itsgeneral principles. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains and which fallwithin the limits of the appended claims.

What is claimed is:
 1. A method of performing a total hip arthroplasty,comprising: making an anterior incision starting over anintertrochanteric ridge and extending obliquely; making a posteriorincision aligned with a femur and substantially collinear with theanterior incision; preparing an acetabulum to receive an prostheticacetabular component through the anterior incision; preparing the femurto receive a prosthetic femoral component; and seating the prostheticacetabular and femoral components.
 2. The method of claim 1, whereinsaid anterior incision is made substantially along a Langer's line. 3.The method of claim 1, wherein said anterior incision has a length ofabout 3.75-5 cm.
 4. The method of claim 1, wherein said anteriorincision has a length of no more than 5 cm.
 5. The method claim 1,wherein said posterior incision has a length of about 2-3 cm.
 6. Themethod of claim 1, wherein said posterior incision has a length of nomore than 5 cm.
 7. The method of claim 1, wherein said anterior incisionextends medially from the intertrochanteric ridge.
 8. A method ofperforming a total hip arthroplasty, comprising: making an anteriorincision starting over an intertrochanteric ridge and extendingobliquely; preparing an acetabulum to receive a prosthetic acetabularcomponent through said anterior incision; hyperextending a hip overwhich the anterior incision is made; preparing a femur to receive aprosthetic femoral component through said anterior incision; and seatinga prosthetic acetabular and a prosthetic femoral component in theacetabulum and the femur, respectively.
 9. The method of claim 8,wherein said anterior incision extends medially from theintertrochanteric ridge.
 10. The method of claim 8, wherein saidanterior incision is made substantially along a Langer's line.
 11. Themethod of claim 8, wherein said anterior incision has a length of about3.75-5 cm.
 12. The method of claim 8, wherein said anterior incision hasa length of no more than 5 cm.
 13. The method of claim 8, wherein saidstep of hyperextending the hip over which the anterior incision is madecomprises hyperextending the hip to about 70° of hyperextension.
 14. Themethod of claim 8, wherein said step of hyperextending the hip overwhich the anterior incision is made comprises hyperextending the hip toabout 70°-80° of hyperextension.
 15. The method of claim 8, wherein saidstep of hyperextending the hip over which the anterior incision is madecomprises hyperextending the hip to about 90° of hyperextension.
 16. Anacetabular cup inserter, comprising: a frame; securing means forsecuring a prosthetic acetabular component to said frame; and animpaction surface, said securing means aligned with said impactionsurface, said frame having an offset frame leg offset from a line formedby said impaction surface and said securing means.
 17. The acetabularcup inserter of claim 16, wherein said securing means comprises athreaded shaft, and wherein said acetabular cup inserter furthercomprises: a drive linkage rotationally connected to said threadedshaft; and lock means for rotationally locking said drive linkage tosaid frame.
 18. The acetabular cup inserter of claim 16, wherein saidthreaded shaft is resiliently retained in a threaded shaft aperture ofsaid frame.
 19. A universal joint, comprising: a male aspect, said maleaspect comprising a multiply sided spheroid; and a female aspect havingan internal aperture with a polygonal cross section, said male aspectpositioned within said internal aperture.
 20. The universal joint ofclaim 19, wherein said male aspect comprises a six sided spheroid andwherein said internal aperture of said female aspect has a hexagonalcross section, and wherein said male aspect is rotationally fixed tosaid female aspect.
 21. In combination, a rasp and rasp handle,comprising: a rasp handle body having a rasp handle proximal end, a rasphandle distal end, and a tapered rasp handle docking aperture formed insaid distal end; a rasp having a rasp proximal end, a rasp distal end,and a post extending from said rasp proximal end; and lock means forsecuring said post within said rasp handle locking aperture.
 22. Thecombination of claim 21, wherein said lock means comprises: a lockingjaw for engaging said post; and actuating means for actuating saidlocking jaw between a locked position in which said post is retainedwithin said rasp handle locking aperture and a release position in whichsaid post is not retained within said rasp handle locking aperture. 23.The combination of claim 22, wherein said locking jaw is pivotallyconnected to said rasp handle body and said actuating means comprises amechanical linkage for rotating said locking jaw between one of thelocked position and the release position.
 24. The combination of claim21, further comprising: an anteversion handle connected to said rasphandle body.
 25. The combination of claim 21, further comprising:anteversion means for establishing a desired rasp anteversion, saidanteversion means connected to said rasp handle body.
 26. Incombination, a rasp and rasp handle, comprising: a rasp handle bodyhaving a rasp handle proximal end, a rasp handle distal end, and a rasphandle docking aperture formed in said distal end; a rasp having a raspproximal end, a rasp distal end, and a post extending from said raspproximal end; and a locking jaw moveable connected to said rasp handlebody, said locking jaw moveable between a locked position in which saidpost is retained within said rasp handle locking aperture and a releaseposition in which said post is not retained within said rasp handlelocking aperture.
 27. The combination of claim 26, wherein said postincludes a notch, said notch engaged by said locking jaw in the lockedposition.
 28. The combination of claim 27, wherein said notch comprisesa V-shaped notch.
 29. The combination of claim 26, further comprising:an anteversion handle connected to said rasp handle body.
 30. Thecombination of claim 26, further comprising: anteversion means forestablishing a desired rasp anteversion, said anteversion meansconnected to said rasp handle body.
 31. An operating table, comprising:a table top; a leg panel formed in said table top, said leg panelrotatable relative to a remaining portion of said table top; and abuttocks door formed in said table top, said buttocks door moveablerelative to said table top to provide an opening through said table top.32. The operating table of claim 31, wherein said buttocks door ishingedly connected to said leg panel.